Christian Heidel, the sporting director for Mainz 05, stated the club is not obligated to sell Kaishu Sano and can afford his retention. Heidel added that many people within the team and the club would be happy if Sano stays. He also emphasized that, in line with the club's standard practice, Mainz 05 would have to consider any offer that is exceptionally good.

Japan international midfielder Kaishu Sano has been linked with a potential transfer to AC Milan. Liverpool and Newcastle United have also been mentioned in connection with the Mainz 05 player. Sano has a contract with the club until 2028, and according to reports in July 2026, Liverpool were prepared to offer up to €60 million for the player.